the second mill has its tramming ring hung like a mariner's compass, in a meal-proof case, with a bridge tree behind, to set it up by means of two temper screws, thus causing the mill to grind either coarse or fine.
     Both mills being on the same shaft, the grinding pressure of one is directly against the other; it therefore does away entirely with the friction on the end of spindle, thereby saving one-third of the power and also the expense of keeping up the parts that wear by said friction.
     These mills grind as fine passing once through as to run through a single mill twice.
It balances perfectly, runs light, does not choke, or heat the shaft or boxes, and the ground feed comes from the mill nice and cool.
                                                        Instructions
      The double mills are just as easily operated as our single mills; nothing complicated about them.
      By the removal of four bolts, the top of the mill case can be turned over and the shaft lifted out and the worn plates replaced by new ones in a few minutes.
      Always have the lower side of the belt the pulling one and set mill from 12 to 20 feet from the driving pulley. The lowest number of revolutions which will take in the quantity desired to be ground in a given time requires the least power.
      When starting the mill always have the plates wide open and allow a small portion of the product, to be ground, to pass through while gradually closing the plates to obtain the required degree of fineness. Also open the plates immediately when you are through grinding, for if they are closed tight with the mill running, and nothing passing through, they wear away quickly. .
      When setting the plates on these double mills, screw up both of the temper or regulating screws as regularly and evenly as possible, so that the plates may be brought to bear evenly upon each other and produce a uniform degree of fineness.